title: Snap-gauge compared to a full nocturnal penile tumescence study for evaluation of patients with erectile impotence.
abstract: A total of 50 consecutive male patients underwent simultaneous Snap-Gauge and full nocturnal penile tumescence evaluation with objective rigidity measurements to determine the correlation between the 2 studies. Subsequent clinical evaluation was conducted in patients in whom the 2 tests differed regarding diagnoses to determine which test more accurately predicted the clinical outcome. One patient was excluded from the study for technical reasons. Of 14 patients who had a normal Snap-Gauge evaluation, defined by breakage of all 3 bands, 12 (86%) had a normal and 2 (14%) had an abnormal nocturnal penile tumescence evaluation. A total of 28 patients failed to break any of the Snap-Gauge bands and 7 broke only 1 or 2 bands. Of these 35 patients with an abnormal Snap-Gauge study 14 (40%) had a normal and 21 (60%) had an abnormal nocturnal penile tumescence evaluation. In a subsequent clinical evaluation 1 of the 2 patients with a normal Snap-Gauge study and an abnormal nocturnal penile tumescence test reported continued inadequate sexual function and, subsequently, he received a penile prosthesis. Of the 14 patients with an abnormal Snap-Gauge study and a normal nocturnal penile tumescence test 11 were located and 8 were sexually active with adequate erections for intercourse without further medical treatment other than counseling. We conclude that the correlation between Snap-Gauge and nocturnal penile tumescence is not good, and that the nocturnal penile tumescence test is more accurate to determine the clinical diagnosis.
authors.affiliation: Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: R
authors.initials: R
authors.lastname: Allen
authors.forename: C B
authors.initials: CB
authors.lastname: Brendler
mesh_terms: D000328:Adult; D000368:Aged; D007172:Erectile Dysfunction / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010410:Penile Erection; D012890:Sleep / Q000502:physiology; D014572:Urology / Q000295:instrumentation